HOFFMAN ESTATES, Ill. (CBS) -- A Hoffman Estates High School student is facing weapons charges after police said he brought a gun to school on Friday.

At 7:40 a.m., the resource officer at the school, 1100 W. Higgins Rd., was called for a fight between three teens. The officer took the teens into custody, and found one of them had a 9mm handgun in a backpack.

The school was placed into lockdown so Hoffman Estates police and school officials could investigate.

The teen with the gun was charged with unlawful possession of a weapon and ammunition on school grounds.

The other teens involved were arrested on disorderly conduct charges.